Description of Problem:
A shared library that uses the stat, fstat etc.functions provided by libc is 
compiled without optimization enabled and without explicitly linking to -lc. 
When a binary is compiled using the above shared library, the binary fails to 
run. Following is the error message:
statest1_g: error while loading shared 
libraries: /samples/redhat/statest/libstatdll1_g.so: undefined symbol: stat

The binary runs fine when compiled using a shared library which is compiled 
with either optimization enabled or explicitly linking to -lc.

Version-Release number of selected component (if applicable):
libc comes with Redhat Linux 7.2

How Reproducible:
It happens consistently. Here is the sample:
1. statest.c
#include <stdio.h>
extern int foo();
int main()
{
        printf("From main\n");
        foo();
}

2. statdll.c
#include <stdio.h>
#include <sys/stat.h>
int foo()
{
        struct stat buf;
        stat("./statest.c", &buf);
        printf("Called stat\n");
        return;
}

3. statdll_g.c
#include <stdio.h>
#include <sys/stat.h>
int foo()
{
        struct stat buf;
        stat("./statest.c", &buf);
        printf("Called stat\n");
        return;
}

4. makefile
all: libstatdll.so libstatdll1.so statest statest1 libstatdll_g.so 
libstatdll1_g.so statest_g statest1_g
statdll.o:      statdll.c
        cc -O -c statdll.c
statdll_g.o: statdll_g.c
        cc -g -c statdll_g.c
libstatdll.so:  statdll.o
        ld -shared -o libstatdll.so statdll.o -lc
libstatdll1.so: statdll.o
        ld -shared -o libstatdll1.so statdll.o
libstatdll_g.so: statdll_g.o
        ld -shared -g -o libstatdll_g.so statdll_g.o -lc
libstatdll1_g.so: statdll_g.o
        ld -shared -g -o libstatdll1_g.so statdll_g.o
statest_g: statest.c
        cc -g -o statest_g statest.c -L./ -lstatdll_g
statest1_g: statest.c
        cc -g -o statest1_g statest.c -L./ -lstatdll1_g
statest: statest.c
        cc -O -o statest statest.c -L./ -lstatdll
statest1: statest.c
        cc -O -o statest1 statest.c -L./ -lstatdll1
clean:
        rm -f *.o *.so statest statest1 *_g

Steps to Reproduce:
1. Build the sample: go to the sample directory, run "make"
2. Set environment variable LD_LIBRARY_PATH to include the sample directory
3. Run "statest" "statest1" "statest_g" and "statest1_g" respectly.

Actual Results:
The first three binaries works fine. statest1_g fails.

Expected Results:
All four binaries should work.


Additional Information:
If I have to explicitly link to -lc, what's the impact to my shared library and 
binary?